C0305

DTC C0305

Steps 1 - 2:

Steps 3 - 12:

Circuit Description
The front propshaft speed sensor is a Permanent Magnet (PM) generator. The PM generator produces a pulsing AC voltage. The AC voltage level and number of pulses increase as speed increases. The transfer case shift control module converts the pulsating AC voltage to a propshaft RPM which is used for calculations, and to monitor the difference between the front and rear propshaft speed. It is also used in the AUTO, Adapt mode of operation to determine the amount of slip and the percent of torque to apply to the front axle. The module only looks at this input when the vehicle is in AUTO, Adapt mode, 4H, and 4L ranges. The propshaft RPM can be displayed with a scan tool.

This DTC detects an open, short to ground, short to voltage or faulty sensor.

Conditions for Running the DTC
^ The ignition is ON.
^ System voltage is 9 - 18 volts.
^ Vehicle speed exceeds 16 km/h (10 mph).

Conditions for Setting the DTC
The system logs the DTC it the front propshaft input indicates a speed of less than 16 RPM for 30 seconds while all of the following are true:
^ The transmission is NOT in PARK/NEUTRAL.
^ The engine is running.
^ The rear propshaft speed exceeds 512 RPM.
^ Vehicle Speed On Class 2 Data bus exceeds 16 km/h (10 mph).

Action Taken When the DTC Sets
^ All shifts to AUTO, Adapt mode are disabled. If the current mode is AUTO, the system does not allow any further adaptive events, correct slip.
^ The SERVICE AWD indicator remains illuminated for the remainder of the current ignition cycle.

Conditions for Clearing the DTC
^ The transfer case shift control module clears the DTC if the condition for setting the DTC no longer exists.
^ A history DTC clears after 100 consecutive ignition cycles without a fault present.
^ History DTCs can be cleared using a scan tool.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step tests to see if the malfunction is intermittent.
3. This step tests the internal resistance of the propshaft speed sensor.
4. This step tests to see if the propshaft speed sensor can generate a sufficient amount of AC voltage.
5. This step tests the front propshaft speed sensor low signal circuit for a short to ground, a high resistance or an open.
6. This step tests the front propshaft speed sensor high signal circuit for a short to ground, a high resistance or an open.
7. This step tests the front propshaft speed sensor low signal circuit for a short to voltage.
8. This step tests the front propshaft speed sensor high signal circuit for a short to voltage.
9. This step tests the front propshaft speed sensor low signal circuit for a short to the front propshaft speed sensor high signal circuit.